A carbon dioxide laser which functions in both rapid superpulsed and continuous wave mode for use in ophthalmic surgery is described. Rapid superpulsed mode was found more effective in the creation of trabeculectomy-like procedures in glaucomatous human eyes with satisfactory results in 12 of 14 eyes treated. Continuous wave energy was found to be superior when full thickness eye wall resection was performed. The carbon dioxide laser was found to be effective in hemostatic resection and ablation of skin lesions about the eye. Rapid superpulse was found to be more effective when puckering and tissue loss were to be minimized, while continuous wave was found to be effective when shrinkage of tissue, as in the performance of a Ziegler cautery type repair for ectropion, was preferred. Rapid superpulse was found to be more controllable in experimental phacovaporization in cats with anterior capsulotomy being easily performed. Continuous wave was found to be a more efficacious modality for corneal shrinkage although attempts at present to create permanent corneal alterations have been fruitless.